Engineering · Mastering
Karl Groom
London, United Kingdom
Karl Groom is credited on 352 releases across 164 albums tracked on Gatefold, active 1990–2026 — the collector-built map of who actually made the music.
352
Pressings credited
164
Albums
4
Decades active
44
In collections
Biography
Karl Groom is a British guitarist and record producer. He is best known as a founding and the only constant member of the progressive metal band Threshold. His production and mixing credits are mainly with progressive and power metal bands.
Bio from Wikipedia
Credited work
352 releases · 164 albums · active 1990–2026
- Engineering · 257
- Mastering · 185
- Production · 150
- Performance · 120
- Other credits · 24
Studios: Thin Ice Studios · Halfway Houses · Dockside Studio, Southampton · Eightspace Studio
Discography
Records they worked on — most-collected first.

Inhuman Rampage
2006

Sonic Firestorm
2004

Subsurface
2004

Hypothetical
2001

Dividing Lines
2022

The Seventh Degree Of Separation
2011

Valley Of The Damned
2003

Critical Mass
2002

Immortal?
2000

Clone
1998

Psychedelicatessen
1994

The Jewel
1985

Wounded Land

Legends Of The Shires
2017

March Of Progress
2012

Pure
2008

Ultra Beatdown
2008

Dead Reckoning
2007

Contagion
2003

Not Of This World
2001

Corruption Within
2000

From A Page
2019

For The Journey
2014

In The Present (Live From Lyon)
2011
Frequent collaborators
- Pendragon (3)
- Threshold (3)
- Galahad
- Lee Abraham
- Arena (11)
- Shadow Keep
- Clive Nolan
- Various
Around the web
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